A mobile body control device adjusts a stop position of a mobile body based on an instruction of a user. The device acquires instruction information for designating a predetermined target and acquires a captured image captured in the mobile body. The device determines a stop position, which is a relative position of the predetermined target measured from the mobile body, where on a region of the predetermined target has been identified in the captured image and control traveling of the mobile body toward the determined stop position. When the predetermined target cannot be identified in the captured image when the mobile body is traveling toward the stop position, the device updates the stop position determined for the predetermined target in accordance with the movement of the mobile body, thereby controlling traveling of the mobile body toward the stop position.